The present invention relates to etching compositions and methods for preparation, and more particularly to an etching composition for glass and a method of making the glass etching composition.
Various etching compositions are known. For example, U.S. Patent No. 3,616,098 teaches a glass composition containing ammonium bifluoride crystals, hydrofluoric acid, potassium fluoride and a solvent system containing water and diethylene glycol or propylene glycol. U.S. Patent No. 4,376,673 teaches a composition for etching dental porcelain which includes a buffered solution containing an alkali metal fluoride such as sodium fluoride dissolved in a dilute weak acid, such as phosphoric acid, lactic acid, acetic acid and citric acid, to provide trace amounts of hydrogen fluoride in the solution. U.S. Patent No 4,517,106 teaches an etching solution particularly adopted to etch integrated circuit components including ammonium bifluoride and an organic solvent such as ethylene glycol.